fix(openai): emulate web_search on /v1/messages for OpenAI API Key accounts

Chat Completions conversion drops Anthropic web_search tools, so Claude
Code's WebSearch on OpenAI-platform groups (e.g. DeepSeek upstreams)
got no web_search_tool_result and reported 0 results. Run the existing
search emulation in ForwardAsAnthropic and let OpenAI API Key accounts
opt in via extra.web_search_emulation.

backend/internal/service/account.go

@@ -2316,7 +2316,10 @@ const (
 // 三态：default（跟随渠道）/ enabled（强制开启）/ disabled（强制关闭）。
 // 兼容旧 bool 值：true→enabled, false→default（并记录 debug 日志）。
 func (a *Account) GetWebSearchEmulationMode() string {
-	if a == nil || a.Platform != PlatformAnthropic || a.Type != AccountTypeAPIKey || a.Extra == nil {
+	// OpenAI API Key accounts reach this via /v1/messages; their upstreams
+	// (DeepSeek etc. over Chat Completions) have no web_search tool.
+	if a == nil || a.Type != AccountTypeAPIKey || a.Extra == nil ||
+		(a.Platform != PlatformAnthropic && a.Platform != PlatformOpenAI) {
 		return WebSearchModeDefault
 	}
 	raw := a.Extra[featureKeyWebSearchEmulation]

backend/internal/service/account_websearch_test.go

@@ -86,12 +86,30 @@ func TestGetWebSearchEmulationMode_MissingField(t *testing.T) {
 	require.Equal(t, WebSearchModeDefault, a.GetWebSearchEmulationMode())
 }
 
-func TestGetWebSearchEmulationMode_NonAnthropicPlatform(t *testing.T) {
+func TestGetWebSearchEmulationMode_OpenAIAPIKey(t *testing.T) {
 	a := &Account{
 		Platform: PlatformOpenAI,
 		Type:     AccountTypeAPIKey,
 		Extra:    map[string]any{featureKeyWebSearchEmulation: "enabled"},
 	}
+	require.Equal(t, WebSearchModeEnabled, a.GetWebSearchEmulationMode())
+}
+
+func TestGetWebSearchEmulationMode_OpenAIOAuth(t *testing.T) {
+	a := &Account{
+		Platform: PlatformOpenAI,
+		Type:     AccountTypeOAuth,
+		Extra:    map[string]any{featureKeyWebSearchEmulation: "enabled"},
+	}
+	require.Equal(t, WebSearchModeDefault, a.GetWebSearchEmulationMode())
+}
+
+func TestGetWebSearchEmulationMode_OtherPlatform(t *testing.T) {
+	a := &Account{
+		Platform: PlatformGemini,
+		Type:     AccountTypeAPIKey,
+		Extra:    map[string]any{featureKeyWebSearchEmulation: "enabled"},
+	}
 	require.Equal(t, WebSearchModeDefault, a.GetWebSearchEmulationMode())
 }
 

backend/internal/service/gateway_websearch_emulation.go

@@ -52,13 +52,22 @@ func getWebSearchManager() *websearch.Manager {
 // Judgment chain: manager exists → only web_search tool → global enabled → account/channel enabled.
 // Account-level mode: "enabled" (force on), "disabled" (force off), "default" (follow channel).
 func (s *GatewayService) shouldEmulateWebSearch(ctx context.Context, account *Account, groupID *int64, body []byte) bool {
-	if getWebSearchManager() == nil {
+	return shouldEmulateWebSearchFor(ctx, s.settingService, s.channelService, account, groupID, body)
+}
+
+// shouldEmulateWebSearchFor is shared by the Anthropic gateway and the OpenAI
+// gateway's /v1/messages path.
+func shouldEmulateWebSearchFor(
+	ctx context.Context, settingService *SettingService, channelService *ChannelService,
+	account *Account, groupID *int64, body []byte,
+) bool {
+	if getWebSearchManager() == nil || account == nil || settingService == nil {
 		return false
 	}
 	if !isOnlyWebSearchToolInBody(body) {
 		return false
 	}
-	if !s.settingService.IsWebSearchEmulationEnabled(ctx) {
+	if !settingService.IsWebSearchEmulationEnabled(ctx) {
 		return false
 	}
 
@@ -69,10 +78,10 @@ func (s *GatewayService) shouldEmulateWebSearch(ctx context.Context, account *Ac
 	case WebSearchModeDisabled:
 		return false
 	default: // "default" → follow channel config
-		if groupID == nil || s.channelService == nil {
+		if groupID == nil || channelService == nil {
 			return false
 		}
-		ch, err := s.channelService.GetChannelForGroup(ctx, *groupID)
+		ch, err := channelService.GetChannelForGroup(ctx, *groupID)
 		if err != nil || ch == nil {
 			return false
 		}
@@ -143,14 +152,21 @@ func extractWebSearchTextFromContent(content gjson.Result) string {
 func (s *GatewayService) handleWebSearchEmulation(
 	ctx context.Context, c *gin.Context, account *Account, parsed *ParsedRequest,
 ) (*ForwardResult, error) {
-	startTime := time.Now()
-
 	// Release the serial queue lock immediately — we don't need upstream.
 	if parsed.OnUpstreamAccepted != nil {
 		parsed.OnUpstreamAccepted()
 	}
+	return writeEmulatedWebSearch(ctx, c, account, parsed.Body.Bytes(), parsed.Model, parsed.Stream)
+}
 
-	query := extractSearchQueryFromBody(parsed.Body.Bytes())
+// writeEmulatedWebSearch runs the search for the last user message and writes
+// an Anthropic Messages response (SSE when stream is true).
+func writeEmulatedWebSearch(
+	ctx context.Context, c *gin.Context, account *Account, body []byte, model string, stream bool,
+) (*ForwardResult, error) {
+	startTime := time.Now()
+
+	query := extractSearchQueryFromBody(body)
 	if query == "" {
 		return nil, fmt.Errorf("web search emulation: no query found in messages")
 	}
@@ -173,12 +189,11 @@ func (s *GatewayService) handleWebSearchEmulation(
 	slog.Info("web search emulation: search completed",
 		"provider", providerName, "results_count", len(resp.Results))
 
-	model := parsed.Model
 	if model == "" {
 		model = defaultWebSearchModel
 	}
 
-	if parsed.Stream {
+	if stream {
 		return writeWebSearchStreamResponse(c, query, resp, model, startTime)
 	}
 	return writeWebSearchNonStreamResponse(c, query, resp, model, startTime)

backend/internal/service/gateway_websearch_emulation_test.go

@@ -378,3 +378,26 @@ func TestShouldEmulateWebSearch_DefaultMode_NilChannelService(t *testing.T) {
 	// nil channelService + default mode → returns false
 	require.False(t, svc.shouldEmulateWebSearch(context.Background(), account, &groupID, webSearchToolBody))
 }
+
+func TestShouldEmulateWebSearchFor_OpenAIAPIKeyAccountEnabled(t *testing.T) {
+	mgr := websearch.NewManager([]websearch.ProviderConfig{{Type: "brave", APIKey: "k"}}, nil)
+	SetWebSearchManager(mgr)
+	defer SetWebSearchManager(nil)
+
+	setGlobalWebSearchConfig(&WebSearchEmulationConfig{
+		Enabled:   true,
+		Providers: []WebSearchProviderConfig{{Type: "brave", APIKey: "k"}},
+	})
+	defer clearGlobalWebSearchConfig()
+
+	settingSvc := newSettingServiceForWebSearchTest(true)
+	account := &Account{
+		ID:       1,
+		Platform: PlatformOpenAI,
+		Type:     AccountTypeAPIKey,
+		Extra:    map[string]any{featureKeyWebSearchEmulation: WebSearchModeEnabled},
+	}
+	groupID := int64(0)
+	require.True(t, shouldEmulateWebSearchFor(context.Background(), settingSvc, nil, account, &groupID, webSearchToolBody))
+	require.False(t, shouldEmulateWebSearchFor(context.Background(), settingSvc, nil, account, &groupID, nonWebSearchToolBody))
+}

backend/internal/service/openai_gateway_messages.go

@@ -45,6 +45,16 @@ func (s *OpenAIGatewayService) ForwardAsAnthropic(
 	rememberOpenCodeInboundBody(c, body)
 	beginUpstreamResponseModelObservation(c)
 	ClearActualOpenAIUpstreamEndpoint(c)
+	// Web Search 模拟：Chat Completions 转换会丢掉 web_search 工具，纯 web_search
+	// 请求在此直接调用搜索 API 构造 Anthropic 响应，不访问上游。
+	if groupID := getOpenAIGroupIDFromContext(c); shouldEmulateWebSearchFor(ctx, s.settingService, s.channelService, account, &groupID, body) {
+		stream := gjson.GetBytes(body, "stream").Bool()
+		res, err := writeEmulatedWebSearch(ctx, c, account, body, gjson.GetBytes(body, "model").String(), stream)
+		if err != nil {
+			return nil, err
+		}
+		return &OpenAIForwardResult{Model: res.Model, Stream: stream, Duration: res.Duration}, nil
+	}
 	if shouldForwardOpenAIResponsesViaRawChatCompletions(account) {
 		SetActualOpenAIUpstreamEndpoint(c, "/v1/chat/completions")
 	}

frontend/src/components/account/EditAccountModal.vue

@@ -2248,9 +2248,9 @@
         </div>
       </div>
 
-      <!-- Anthropic API Key: Web Search Emulation (hidden when global disabled) -->
+      <!-- Anthropic / OpenAI API Key: Web Search Emulation (hidden when global disabled) -->
       <div
-        v-if="account?.platform === 'anthropic' && account?.type === 'apikey' && webSearchGlobalEnabled"
+        v-if="(account?.platform === 'anthropic' || account?.platform === 'openai') && account?.type === 'apikey' && webSearchGlobalEnabled"
         class="border-t border-gray-200 pt-4 dark:border-dark-600"
       >
         <div class="flex items-center justify-between">
@@ -4425,6 +4425,8 @@ const syncFormFromAccount = (newAccount: Account | null) => {
     anthropicAPIKeyAuthScheme.value = extra?.anthropic_apikey_auth_scheme === 'authorization_bearer'
       ? 'authorization_bearer'
       : 'x_api_key'
+  }
+  if ((newAccount.platform === 'anthropic' || newAccount.platform === 'openai') && newAccount.type === 'apikey') {
     // 三态：string "default"/"enabled"/"disabled"，向后兼容旧 bool
     const wsVal = extra?.web_search_emulation
     if (wsVal === 'enabled' || wsVal === 'disabled') {
@@ -5932,6 +5934,11 @@ const handleSubmit = async () => {
           newExtra.images_url_to_b64_json = true
         } else {
           delete newExtra.images_url_to_b64_json
+        }
+        if (webSearchEmulationMode.value === 'default') {
+          delete newExtra.web_search_emulation
+        } else {
+          newExtra.web_search_emulation = webSearchEmulationMode.value
         }
 		}
 		if (autoPause5hThreshold.value != null && autoPause5hThreshold.value > 0) {